All of a sudden my default message for my invoices is not apply automatically anymore. It was before but no longer is. Please let me know how to fix it?

I understand that default messages can be helpful and convenient for you, @cataldi22. Let me share some insights to sort out this matter at hand.

To ensure that your invoice's default message is set up correctly, please check and review the Messages section in your Sales settings. You can find this option in the Account and Settings. Here's how you can check it:

1. Go to Settings.
2. Select Account and settings, and click Sales tab.
3. Select the edit (pencil icon) in the Messages section.
4. From the Sales form dropdown under Blind Copy (Bcc) new invoices to address, select Invoices and other sales forms, and type the default message to customers.
5. Hit Save, then Done. 

Furthermore, if you'd like to learn about how to send invoice reminders to customers and receive invoice payments in QuickBooks Online (QBO), you can refer to this article for future reference:

•  Create invoices in QuickBooks Online
• Send invoice reminders automatically or manually in QuickBooks Online

Please let us know when you're experiencing challenges with the process and still need further help about adding default messages in QBO. We'll take care of them for you. Have a good one.